Tuning a metamaterial switch without external stimuli

Metamaterials are engineered to exhibit unusual properties, such as band gaps that block mechanical vibrations of certain frequencies. While these properties can be tuned, adjusting and maintaining a metamaterial’s various states typically requires continuous external stimuli.

Majid Kheybari and Hongyi Xu introduced a design for a metamaterial switch that can transition between six states, each corresponding to a fixed band gap, without the need for external stimuli. Computational studies of the switch’s behavior showed that changing the configuration of its unit cells changes the location of the band gaps, allowing for precise control of the propagation of mechanical vibrations over a broad spectrum.

This design offers a method of vibration isolation, noise reduction, and waveguiding for fields that require full functioning despite power outages. For example, this design could be used to develop metamaterials that block unwanted vibrations from interfering with precision medical devices, microelectronics, and military equipment.

“One of the reasons we are particularly excited about this switch is that it can operate without the need for external stimuli or power sources, which reduces energy consumption, packaging complexity, and overall system cost,” Xu said. “Importantly, the simple and reproducible design of our switch makes it well suited for fabrication using additive manufacturing technologies, such as 3D printing. This allows for production in various physical sizes and the use of different materials, enabling easy adaptation to different systems and applications.”

In their analysis, the authors also combined multiple switches to form supercells, which allowed for further customization of mechanical vibration propagation. Next, they will investigate which supercell configurations yield the best properties for a topological insulator.

Source: “Multi-position metamaterial switch enables adjustable band gaps for guiding elastic waves,” by Majid Kheybari and Hongyi Xu, AIP Advances (2025). The article can be accessed at https://doi.org/10.1063/5.0256329 .